1. Field of the Invention
The present invention relates to a nanoporous membrane and a method of fabricating the same, and more particularly, to a nanoporous membrane including a support and a separation layer having a plurality of nano-sized pores at a density of 1010/cm2 or greater and a matrix.
2. Description of the Related Art
Membrane filtration technologies are widely used throughout almost all industrial fields, for example, to produce ultrapure water in the electronics field, to separate medicines, such as protein, enzyme, antibody, etc., in the biotechnology field, or in a concentration process in the food industry. Membrane filtration technologies can be classified into microfiltration, ultrafiltration, nanofiltration, etc., according the size of a material to be filtered.
In general, membranes used in such filtration technologies can be manufactured using polymer. A method of manufacturing a filtration membrane is disclosed in Korean Patent Laid-open No. 10-2005-0029603. Membrane manufacturing processes can be classified into processes of manufacturing a membrane having a nominal pore size and processes of manufacturing a membrane having an absolute pore size. Processes of manufacturing a membrane having a nominal pore size involve stretching, interfacial polymerization, phase-inversion, etc. Processes of manufacturing a membrane having an absolute pore size involve track-etching in which pores are formed through the irradiation of a radioactive element and corrosion for a predetermined time.
A membrane having a nominal pore size includes pores which are abnormally larger than the nominal pore size, has poor pore size uniformity on the surface thereof, and thus cannot be used to separate or purify a particular material with a high purity. Meanwhile, a membrane having an absolute pore size has high pore size uniformity on the surface thereof and thus can purify a material with a desired high purity. However, the membrane having an absolute pore size has a low surface pore density and a thick separation layer, which lower the flux of the membrane. Therefore, an improvement in this regard is required.